diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp index 8fe82118c4e..8f03707f170 100644 --- a/lib/Target/X86/X86ISelLowering.cpp +++ b/lib/Target/X86/X86ISelLowering.cpp @@ -12792,6 +12792,7 @@ GetTLSADDR(SelectionDAG &DAG, SDValue Chain, GlobalAddressSDNode *GA, // TLSADDR will be codegen'ed as call. Inform MFI that function has calls. MFI->setAdjustsStack(true); + MFI->setHasCalls(true); SDValue Flag = Chain.getValue(1); return DAG.getCopyFromReg(Chain, dl, ReturnReg, PtrVT, Flag); diff --git a/test/CodeGen/X86/tls-addr-non-leaf-function.ll b/test/CodeGen/X86/tls-addr-non-leaf-function.ll new file mode 100644 index 00000000000..ec47232059f --- /dev/null +++ b/test/CodeGen/X86/tls-addr-non-leaf-function.ll @@ -0,0 +1,37 @@ +; RUN: llc < %s -relocation-model=pic -O2 -disable-fp-elim -o - | FileCheck %s +; RUN: llc < %s -relocation-model=pic -O2 -o - | FileCheck %s + +; This test runs twice with different options regarding the frame pointer: +; first the elimination is disabled, then it is enabled. The disabled case is +; the "control group". +; The function 'foo' below is marked with the "no-frame-pointer-elim-non-leaf" +; attribute which dictates that the frame pointer should not be eliminated +; unless the function is a leaf (i.e. it doesn't call any other function). +; Now, 'foo' is not a leaf function, because it performs a TLS access which on +; X86 ELF in PIC mode is expanded as a library call. +; This call is represented with a pseudo-instruction which doesn't appear to be +; a call when inspected by the analysis passes (it doesn't have the "isCall" +; flag), and the ISel lowering code creating the pseudo was not informing the +; MachineFrameInfo that the function contained calls. This affected the decision +; whether to eliminate the frame pointer. +; With the fix, the "hasCalls" flag is set in the MFI for the function whenever +; a TLS access pseudo-instruction is created, so 'foo' appears to be a non-leaf +; function, and the difference in the options does not affect codegen: both +; versions will have a frame pointer. + +; Test that there's some frame pointer usage in 'foo'... +; CHECK: foo: +; CHECK: pushq %rbp +; CHECK: movq %rsp, %rbp +; ... and the TLS library call is also present. +; CHECK: leaq x@TLSGD(%rip), %rdi +; CHECK: callq __tls_get_addr@PLT + +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +@x = thread_local global i32 0 +define i32 @foo() "no-frame-pointer-elim-non-leaf" { + %a = load i32* @x, align 4 + ret i32 %a +}